holden hz 350 overlander conversion

[Dazza92VP]

ok so its finally up to the stage were we could start it harness is all convolute tubed and cleaned upmanaged to get the 3 bar bosch map sensor to work and we found that a harley davidson oil reservoir makes a perfect surge tank comes pre polished perfect mounting holes and free of charge with fittings. so we tried to start it wouldnt even fire not even a pop so started looking at the wiring thinking theres a fault. but its got spark and wiring all tests out fine even had the first dizzy we modded just hooked up to the ignition to spin over by hand so see if the ecm is picking up rpm and the injectors a pulsing and that was fine but after rotating the dizzy a fair few times then plugging in the the proper dizzy and cranking it it fire up and ran but baddly due to timing being out so we figured turn it off get the timing light all set up then start it but once again wouldnt start again after just a few minutes of sitting not even a pop again only runs after having the other dizzy turned buy hand dumping in the fuel. the injectors we are running are 29lb/hr using the injector spread sheet comes out to about 0.102 kinjflow just need to know which table should be bumping up to throw extra fuel in at cranking?

[Dazza92VP]

also couldn't find an xdf to BKBK $3C 5.7L vr v8 to try and rob some of the info out of it for a starting point

[VL400]

the injectors we are running are 29lb/hr using the injector spread sheet comes out to about 0.102 kinjflow just need to know which table should be bumping up to throw extra fuel in at cranking?

There are two tables to adjust, a first stage and second stage cranking PW table. It does not use kinjflow, they are actual PWs in milli-seconds. Search for items starting with "Crank" in TunerPro, there are a handful of scalars and two tables.

[Holden202T]

if anything bigger injectors should mean those tables are to high so it will be putting more in than less!

[Dazza92VP]

That's what I thought but the I considered the maps are setup for a 304 not a 350 so maybe even though injectors are bigger the cranking tables weren't up enough

[Holden202T]

well from some quick maths, your looking at 15% more for the engine size increase, and the injector size difference should flow approx. 45% more for a given pulse width, so in theory you if you had a 1ms cranking PW, taking into account injector size and motor size then you will be looking at 1.67 time more fuel than you need I think.

so what you should do, get the crank table, then multiply it by .70 .... this should get it very close. but its going to be a bit of trial and error, but you can usually hear if the motor starts flooded it will be rough and clear after a bit, but if it takes a lot of time to crank before firing then it might need a bit more.

[Dazza92VP]

you can crank it for as long as you like but it wont even fire or give the hint of firing until you put something down its throat or plug in the other dizzy turn it over buy hand a fair few times to get the injectors to pulse and the pumps going then plug the actual dizzy in and crank it even then it back fires a couple of time and runs like a pig but thats prob because we havent gotten it going to set the dizzy timing

[vs ss]

Hi I know this might be a stupid question but has it got enough fuel pressure at the rail?

[VL400]

To set the timing initially, can set the engine to 10* BTDC and line the reluctor pickup with the middle of a tooth (this normally gets you to within +-5 degrees which is fine to get a start), or crank it with the plugs out to set the timing with a light (plugs in works too just can be slow to get a consistent flash). Need to check that your firing the correct cyl too, its easy to get the dizzy 180 out and have it backfire while cranking.

You can also log it while cranking. Should see a fairly stable 100-200 RPM, if its dropping out might be why it wont start without a guts full.

[Dazza92VP]

ill set up the crank as you said with the reluctor teeth dont know when ill be able to get to it again though maybe wednesday night. the dizzy is definitely setup on correct cycle. with the logging though it drops the connection to the ecm during cranking then as soon as cranking has stopped its fine again i dont know maybe im loosing power to the ecm during cranking but when its got a belly full it just happens to fire using the ignition module to push it further once cranking has stopped should i be able to see the injector drive pulsing with a test light while cranking or not or can i only check with a noid light